Hamptons real estate has strongest summer since 2005

This two-story oceanfront home in Amagansett recently sold for $11 million. It has four bedrooms, two baths and a tennis court.

Real estate sales in the Hamptons posted the strongest third-quarter results in eight years, showing that the wealthy continued to spend on trophy beach homes through the end of the summer.

The total number of sales rose 32 percent in the third quarter, to 534 from 405 a year earlier. The average sales price hit $1,470,565, up 3 percent.

The third quarter is typically a slower sales month in the highly seasonal Hamptons market, the summer playground for New York's wealthy. Spring and late winter tend to be the biggest sales months. And sales did moderate—down 21 percent—from a scorching second quarter, which was the highest on record for the area.

The top of the Hamptons market was especially strong in the latest quarter. Among the top 10 percent of sales, the average price jumped 32 percent compared with the same quarter a year ago, and the median price was up 14 percent. The number of deals jumped 27 percent.

Two of the top sales in the quarter included an oceanfront home in Amagansett with four bedrooms, two baths and a tennis court, which went for $11 million, and a property in East Hampton with five bedrooms, five baths and an in-ground pool that went for $4.3 million.

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Despite the signs of strength, there are also some reasons for caution. As prices and demand have surged, so has inventory. At the high end, inventory in the Hamptons more than doubled in the quarter compared with the same quarter a year ago.